Neither Google Maps nor MSN Virtual Earth records the state of a particular map view on the browser’s URL-line. Google Maps hides all the parameters. MSN Virtual Earth presents only a GUID whose purpose I don’t yet understand, but which doesn’t record the map’s state. In both cases, the stateful URL is found elsewhere than on the URL-line. Google Maps presents it directly, with a link icon and a Link to this page label. MSN Virtual Earth presents it indirectly — clicking Permalink leads to a popup window containing the stateful URL.

The conclusion is that while users still expect URLs to record state, AJAX applications that partially refresh pages will instead need to place the stateful URL somewhere within the page, at a location — and using a style — that will become well-known conventions.